Boston Scientific's stock has doubled on high hopes for the company's new drug-coated stent. Obviously, nobody expects anything to go the least bit wrong.

ONLY A SPOILSPORT would take issue with a large, liquid stock whose earnings could more than double next year, right?

But shares of medical device maker Boston Scientific, which hit an all-time high Tuesday, already have more than doubled over the past 52 weeks, and they appear to be pricing in the entire windfall expected from the company's hot new drug-coated stent.